The invention primarily relates to a method for the preparation of a spread containing lactoprotein and/or vegetable protein and thickener, in which an emulsion is formed which comprises a continuous fat phase and a discontinuous aqueous phase and in which all of the protein and thickener is present in the aqueous phase.
A method of this type is disclosed in Netherlands published Patent Application 177 729.
In the said publication it is described that in order to prepare a low-calorie spread, a solution of gelatine or the like in a protein-free aqueous medium in an amount, based on the total weight of the spread, which depends on the hardness of the fat used is first prepared. Another solution is then prepared in which lactoprotein is dissolved or dispersed. The two resulting solutions are then added together in such a way that the lactoprotein is not exposed to a temperature which is higher than 40.degree. C. The combined aqueous composition thus obtained is then emulsified with a suitable plastic fat composition to obtain a water-in-oil emulsion, which is then cooled and further processed.
A method of this type has the disadvantage in that during the preparation of the combined aqueous composition great care must be taken with regard to the temperature; if the temperature rises above 40.degree. C., in particular when the combined aqueous composition is in the lower pH range, it will be possible for the protein to flocculate out, as a consequence of which the mouth feel of the spread subsequently obtained will be adversely affected.
The temperature must also be carefully controlled during the subsequent formation of the total emulsion; the temperature may then be 30.degree. C. to 60.degree. C., but may only be a maximum of 50.degree. C. if the pH value of the aqueous phase is no higher than 5.2 and if no deflocculating agents are present.
The aim of the present invention is to provide a method which is much less sensitive in respect of the temperature control, so that formation of a product of lesser quality is substantially avoided.